Rats were trained on a fixed ratio 5 (FR 5) for 0.01 ml water reinforcer, a fixed ratio 20 (FR 20) fir 0.01 ml water reinforcer, a fixed ratio 20 (FR 20) for 0.04 ml water reinforcer, a variable time 15 sec (VT 15 sec) for 0.01 ml water reinforcer, a variable time 30 sec (VT 30 sec) for 0.01 ml water, variable time 60 sec (VT 60 sec) for 0.01 ml water, or a variable time 60 sec (VT 60 sec) for 0.10 ml water. In all these schedules, the rate of NE metabolism varied with the number of water presentations but not with the number of responses or the volume of water. The rate of metabolism of DA was increased over control values in rats on the VT schedules but no significant differences could be found in DA metabolism among the rats performing on the various VT schedules or receiving various volumes.
- Brain catecholamine metabolism
- Nonadrenergic neuronal activity
- Schedules of reinforcement
- Tyrosine-hydroxylase inhibitor